package net.wanho.controller;

import lombok.RequiredArgsConstructor;
import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.UUID;

/**
 * Author：汤小洋
 * Date：2025-09-23 13:35
 * Description：<描述>
 */
@RestController
@RequiredArgsConstructor
public class LockController {

    private final StringRedisTemplate redisTemplate;
    private final RedissonClient redissonClient;

    /**
     * 下单时判断库存：从redis中获取库存，检查库存是否够，库存数量>0才允许下单，此时库存数量-1
     */
    @RequestMapping("/deductStock")
    public String deductStock(){
        System.out.println(Thread.currentThread().getName() + "线程正在下单。。。。。。");

        // 加锁，使用Redisson实现分布式锁
        String lockName = "stock_lock"; // 锁的名称
        RLock rLock = redissonClient.getLock(lockName);
        rLock.lock(); // 加锁，锁的过期时间是30秒

        int total = Integer.parseInt(redisTemplate.opsForValue().get("stock"));
        if(total>0){
            try {
                Thread.sleep(5000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            total = total-1;
            redisTemplate.opsForValue().set("stock",String.valueOf(total));
            rLock.unlock(); // 释放锁
            return "下单成功，库存还剩："+total;
        }
        rLock.unlock(); // 释放锁
        return "下单失败，库存不足！";
    }

}
